vfw.cxx

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    //returns object with gray color pallet if needed for 8 bpp formats
    PVideoDeviceBitmap(HWND hWnd, WORD bpp);
    // does not build color pallet
    PVideoDeviceBitmap(HWND hWnd); 
    // apply video format to capture device
    PBoolean ApplyFormat(HWND hWnd, const FormatTableEntry & formatTableEntry);

    BITMAPINFO * operator->() const 
    { return (BITMAPINFO *)theArray; }
};

PVideoDeviceBitmap::PVideoDeviceBitmap(HWND hCaptureWindow)
{
  PINDEX sz = capGetVideoFormatSize(hCaptureWindow);
  SetSize(sz);
  if (!capGetVideoFormat(hCaptureWindow, theArray, sz)) { 
    PTRACE(1, "PVidInp\tcapGetVideoFormat(hCaptureWindow) failed - " << ::GetLastError());
    SetSize(0);
    return;
  }
}

PVideoDeviceBitmap::PVideoDeviceBitmap(HWND hCaptureWindow, WORD bpp)
{
  PINDEX sz = capGetVideoFormatSize(hCaptureWindow);
  SetSize(sz);
  if (!capGetVideoFormat(hCaptureWindow, theArray, sz)) { 
    PTRACE(1, "PVidInp\tcapGetVideoFormat(hCaptureWindow) failed - " << ::GetLastError());
    SetSize(0);
    return;
  }

  if (8 == bpp && bpp != ((BITMAPINFO*)theArray)->bmiHeader.biBitCount) {
    SetSize(sizeof(BITMAPINFOHEADER)+sizeof(RGBQUAD)*256);
    RGBQUAD * bmiColors = ((BITMAPINFO*)theArray)->bmiColors;
    for (int i = 0; i < 256; i++)
      bmiColors[i].rgbBlue  = bmiColors[i].rgbGreen = bmiColors[i].rgbRed = (BYTE)i;
  }
  ((BITMAPINFO*)theArray)->bmiHeader.biBitCount = bpp;
}

PBoolean PVideoDeviceBitmap::ApplyFormat(HWND hWnd, const FormatTableEntry & formatTableEntry)
{
  // NB it is necessary to set the biSizeImage value appropriate to frame size
  // assume bmiHeader.biBitCount has already been set appropriatly for format
  BITMAPINFO & bmi = *(BITMAPINFO*)theArray;
  bmi.bmiHeader.biPlanes = 1;

  int height = bmi.bmiHeader.biHeight<0 ? -bmi.bmiHeader.biHeight : bmi.bmiHeader.biHeight;
  bmi.bmiHeader.biSizeImage = height*4*((bmi.bmiHeader.biBitCount * bmi.bmiHeader.biWidth + 31)/32);

  // set .biHeight according to .negHeight value
  if (formatTableEntry.negHeight)
    bmi.bmiHeader.biHeight = -height; 

#if PTRACING
  PTimeInterval startTime = PTimer::Tick();
#endif

  if (capSetVideoFormat(hWnd, theArray, GetSize())) {
    PTRACE(3, "PVidInp\tcapSetVideoFormat succeeded: "
            << PString(formatTableEntry.colourFormat) << ' '
            << bmi.bmiHeader.biWidth << "x" << bmi.bmiHeader.biHeight
            << " sz=" << bmi.bmiHeader.biSizeImage << " time=" << (PTimer::Tick() - startTime));
    return PTrue;
  }

  if (formatTableEntry.negHeight) {
    bmi.bmiHeader.biHeight = height; 
    if (capSetVideoFormat(hWnd, theArray, GetSize())) {
      PTRACE(3, "PVidInp\tcapSetVideoFormat succeeded: "
              << PString(formatTableEntry.colourFormat) << ' '
              << bmi.bmiHeader.biWidth << "x" << bmi.bmiHeader.biHeight
              << " sz=" << bmi.bmiHeader.biSizeImage << " time=" << (PTimer::Tick() - startTime));
      return PTrue;
    }
  }

  PTRACE(1, "PVidInp\tcapSetVideoFormat failed: "
          << (formatTableEntry.colourFormat != NULL ? formatTableEntry.colourFormat : "NO-COLOUR-FORMAT") << ' '
          << bmi.bmiHeader.biWidth << "x" << bmi.bmiHeader.biHeight
          << " sz=" << bmi.bmiHeader.biSizeImage << " time=" << (PTimer::Tick() - startTime)
          << " - lastError=" << ::GetLastError());
  return PFalse;
}

///////////////////////////////////////////////////////////////////////////////

PCapStatus::PCapStatus(HWND hWnd)
{
  memset(this, 0, sizeof(*this));
  if (capGetStatus(hWnd, this, sizeof(*this)))
    return;

  PTRACE(1, "PVidInp\tcapGetStatus: failed - " << ::GetLastError());
}


///////////////////////////////////////////////////////////////////////////////
// PVideoInputDevice_VideoForWindows

PCREATE_VIDINPUT_PLUGIN(VideoForWindows);

PVideoInputDevice_VideoForWindows::PVideoInputDevice_VideoForWindows()
{
  captureThread = NULL;
  hCaptureWindow = NULL;
  lastFramePtr = NULL;
  lastFrameSize = 0;
  isCapturingNow = PFalse;
}

PBoolean PVideoInputDevice_VideoForWindows::Open(const PString & devName, PBoolean startImmediate)
{
  Close();

  operationMutex.Wait();

  deviceName = devName;

  captureThread = PThread::Create(PCREATE_NOTIFIER(HandleCapture), 0,
                                  PThread::NoAutoDeleteThread, PThread::NormalPriority,
                                  "VidIn:%x");

  operationMutex.Signal();
  threadStarted.Wait();

  PWaitAndSignal mutex(operationMutex);

  if (hCaptureWindow == NULL) {
    delete captureThread;
    captureThread = NULL;
    return PFalse;
  }

  if (startImmediate)
    return Start();

  return PTrue;
}


PBoolean PVideoInputDevice_VideoForWindows::IsOpen() 
{
  return hCaptureWindow != NULL;
}


PBoolean PVideoInputDevice_VideoForWindows::Close()
{
  PWaitAndSignal mutex(operationMutex);

  if (!IsOpen())
    return PFalse;
 
  Stop();

  ::PostThreadMessage(captureThread->GetThreadId(), WM_QUIT, 0, 0L);

  // Some brain dead drivers may hang so we provide a timeout.
  if (!captureThread->WaitForTermination(5000))
  {
      // Two things may happen if we are forced to terminate the capture thread:
      // 1. As the VIDCAP window is associated to that thread the OS itself will 
      //    close the window and release the driver
      // 2. the driver will not be released and we will not have video until we 
      //    terminate the process
      // Any of the two ios better than just hanging
      captureThread->Terminate();
      hCaptureWindow = NULL;
      PTRACE(1, "PVidInp\tCapture thread failed to stop. Terminated");
  }

  delete captureThread;
  captureThread = NULL;

  return PTrue;
}


PBoolean PVideoInputDevice_VideoForWindows::Start()
{
  PWaitAndSignal mutex(operationMutex);

  if (IsCapturing())
    return PTrue;

#if STEP_GRAB_CAPTURE
  isCapturingNow = PTrue;
  return capGrabFrameNoStop(hCaptureWindow);
#else
  if (capCaptureSequenceNoFile(hCaptureWindow)) {
    PCapStatus status(hCaptureWindow);
    isCapturingNow = status.fCapturingNow;
    return isCapturingNow;
  }

  lastError = ::GetLastError();
  PTRACE(1, "PVidInp\tcapCaptureSequenceNoFile: failed - " << lastError);
  return PFalse;
#endif
}


PBoolean PVideoInputDevice_VideoForWindows::Stop()
{
  PWaitAndSignal mutex(operationMutex);

  if (!IsCapturing())
    return PFalse;
  isCapturingNow = PFalse;
#if STEP_GRAB_CAPTURE
  return IsOpen() && frameAvailable.Wait(1000);
#else
  if (capCaptureStop(hCaptureWindow))
    return PTrue;

  lastError = ::GetLastError();
  PTRACE(1, "PVidInp\tcapCaptureStop: failed - " << lastError);
  return PFalse;
#endif
}


PBoolean PVideoInputDevice_VideoForWindows::IsCapturing()
{
  return isCapturingNow;
}


PBoolean PVideoInputDevice_VideoForWindows::SetColourFormat(const PString & colourFmt)
{
  PWaitAndSignal mutex(operationMutex);

  if (!IsOpen())
    return PVideoDevice::SetColourFormat(colourFmt); // Not open yet, just set internal variables

  PBoolean running = IsCapturing();
  if (running)
    Stop();

  PString oldFormat = colourFormat;

  if (!PVideoDevice::SetColourFormat(colourFmt))
    return PFalse;

  PINDEX i = 0;
  while (FormatTable[i].colourFormat != NULL && !(colourFmt *= FormatTable[i].colourFormat))
    i++;

  PVideoDeviceBitmap bi(hCaptureWindow, FormatTable[i].bitCount);

  if (FormatTable[i].colourFormat != NULL)
    bi->bmiHeader.biCompression = FormatTable[i].compression;
  else if (colourFmt.GetLength() == 4)
    bi->bmiHeader.biCompression = mmioFOURCC(colourFmt[0],colourFmt[1],colourFmt[2],colourFmt[3]);
  else {
    bi->bmiHeader.biCompression = 0xffffffff; // Indicate invalid colour format
    PVideoDevice::SetColourFormat(oldFormat);
    return PFalse;
  }

  // set frame width and height
  bi->bmiHeader.biWidth = frameWidth;
  bi->bmiHeader.biHeight = frameHeight;
  if (!bi.ApplyFormat(hCaptureWindow, FormatTable[i])) {
    lastError = ::GetLastError();
    PVideoDevice::SetColourFormat(oldFormat);
    return PFalse;
  }

  // Didn't do top down, tell everything we are up side down
  nativeVerticalFlip = FormatTable[i].negHeight && bi->bmiHeader.biHeight > 0;

  if (running)
    return Start();

  return PTrue;
}


PBoolean PVideoInputDevice_VideoForWindows::SetFrameRate(unsigned rate)
{
  PWaitAndSignal mutex(operationMutex);

  if (!PVideoDevice::SetFrameRate(rate))
    return PFalse;

  if (!IsOpen())
    return PTrue; // Not open yet, just set internal variables

  PBoolean running = IsCapturing();
  if (running)
    Stop();

  CAPTUREPARMS parms;
  memset(&parms, 0, sizeof(parms));

  if (!capCaptureGetSetup(hCaptureWindow, &parms, sizeof(parms))) {
    lastError = ::GetLastError();
    PTRACE(1, "PVidInp\tcapCaptureGetSetup: failed - " << lastError);
    return PFalse;
  }

  // keep current (default) framerate if 0==frameRate   
  if (0 != frameRate)
    parms.dwRequestMicroSecPerFrame = 1000000 / frameRate;
  parms.fMakeUserHitOKToCapture = PFalse;
  parms.wPercentDropForError = 100;
  parms.fCaptureAudio = PFalse;
  parms.fAbortLeftMouse = PFalse;
  parms.fAbortRightMouse = PFalse;
  parms.fLimitEnabled = PFalse;

  if (!capCaptureSetSetup(hCaptureWindow, &parms, sizeof(parms))) {
    lastError = ::GetLastError();
    PTRACE(1, "PVidInp\tcapCaptureSetSetup: failed - " << lastError);
    return PFalse;
  }
    
  if (running)
    return Start();

  return PTrue;
}


PBoolean PVideoInputDevice_VideoForWindows::SetFrameSize(unsigned width, unsigned height)
{
  PWaitAndSignal mutex(operationMutex);

  if (!IsOpen())
    return PVideoDevice::SetFrameSize(width, height); // Not open yet, just set internal variables

  PBoolean running = IsCapturing();
  if (running)
    Stop();

  PVideoDeviceBitmap bi(hCaptureWindow); 
  PTRACE(5, "PVidInp\tChanging frame size from "
         << bi->bmiHeader.biWidth << 'x' << bi->bmiHeader.biHeight << " to " << width << 'x' << height);

  PINDEX i = 0;
  while (FormatTable[i].colourFormat != NULL && !(colourFormat *= FormatTable[i].colourFormat))
    i++;

  bi->bmiHeader.biWidth = width;
  bi->bmiHeader.biHeight = height;
  if (!bi.ApplyFormat(hCaptureWindow, FormatTable[i])) {
    lastError = ::GetLastError();
    return PFalse;
  }

  // Didn't do top down, tell everything we are up side down
  nativeVerticalFlip = FormatTable[i].negHeight && bi->bmiHeader.biHeight > 0;

  // verify that the driver really took the frame size
  if (!VerifyHardwareFrameSize(width, height)) 
    return PFalse; 

  // frameHeight must be positive regardlesss of what the driver says
  if (0 > (int)height) 
    height = (unsigned)-(int)height;

  if (!PVideoDevice::SetFrameSize(width, height))
    return PFalse;

  if (running)
    return Start();

  return PTrue;
}


PBoolean PVideoInputDevice_VideoForWindows::TestAllFormats()
{
  PBoolean running = IsCapturing();
  if (running)
    Stop();

  for (PINDEX prefFormatIdx = 0; FormatTable[prefFormatIdx].colourFormat != NULL; prefFormatIdx++) {
    PVideoDeviceBitmap bi(hCaptureWindow, FormatTable[prefFormatIdx].bitCount); 
    bi->bmiHeader.biCompression = FormatTable[prefFormatIdx].compression;
    for (PINDEX prefResizeIdx = 0; prefResizeIdx < PARRAYSIZE(winTestResTable); prefResizeIdx++) {
      bi->bmiHeader.biWidth = winTestResTable[prefResizeIdx].device_width;